The use of rotary drums for the preheating of glass batch prior to its introduction into a glass melting furnace has been proposed in several patents issued to the assignee of this invention. For example, see U.S. Pat. Nos. 4,319,903 and 4,409,011. In each of these patents, the particulate glass batch is introduced into the upper end of a drum which is rotatable about an inclined axis and a heat exchange medium, such as alumina balls, are introduced into the other, lower end of the drum. The alumina balls are preheated, preferably with the exhaust gases from a glass melting furnace, and the countercurrent flow of the glass batch and heated balls through the drum preheats the glass batch prior to its introduction into the glass melting furnace. The preheated batch is removed from the perforate lower end of the inclined drum, and the cooled media is elevated interiorly of the drum by means of a scroll to be discharged axially of the drum at the upper end of the drum.